It is possible to generate shadows on a static object using ray-tracing, but this is computationally expensive. For three-dimensional computer generated characters which move (e.g. under the control of a user) the generation of shadows, and more generally lighting data, needs to be performed in real-time (i.e. as the character moves) and this means that the available computational resource is limited.
The embodiments described below are not limited to implementations which solve any or all of the disadvantages of known systems and methods for generating lighting data for three-dimensional computer generated characters.